Conductive Keratoplasty (CK)
Conductive keratoplasty or CK is a technique for correcting
farsightedness or hyperopia, and presbyopia. Radiofrequency
energy is applied to the peripheral portions of the
cornea, in a ring-pattern of 8 to 24 spots, using a
needle. The energy creates heat which causes shrinkage
of corneal tissue. The net effect is that the peripheral
cornea is flattened, but the central cornea is steepened.
This results in more focusing power, correcting farsightedness.
Like LTK (laser thermokeratoplasty, which is no longer
used), CK has exhibited regression over time; that is,
the initial result decreases over time. It appears that
the range of correction achievable with CK may be limited
to 1.50 diopters of correction.
CK has also been approved in the treatment of presbyopia,
the reading vision problem that affects persons over
40 years of age. When CK is used for this purpose, one
of a person’s two eyes, the non-dominant eye (the
eye that is the preferred eye is called the dominant
eye; the non-dominant eye is the other one), is purposely
made near-sighted. This eye is used for reading and
near tasks (the distance vision in this eye is not clear);
the other or dominant eye is used for distance vision.
This is a variation on what is called monovision, a
technique which is also used with Lasik.
CK is being primarily marketed to patients who can
see clearly at distance, but have trouble at near (the
over-40 set). Patients may need to be retreated as they
age. It does not allow each eye to see both distance